Collapsible mast erection



1942- H. J. WOTOLSLAYER a-rm. 2,271,573

COLLAPS IBLE MAST ERECTION FiledrAug. 22, 1941 Patented Feb. 3, 1942 COLLAPSIBLE MAST ERECTION Homer J. Woolslayer, Erwin A. Campbell, and

Cecil Jenkins, Tulsa, Okla., assignors to Lee C. Moore & Company, Inc., Pittsburgh, Pa., a corporation of Pennsylvania Application August 22, 1941, Serial No. 407,923

7 Claims.

This invention relates to masts or derricks that are adapted to be assembled in sections on the ground and then swung upwardly into upright position. More particularly the invention pertains to the type of mast shown in Patent No. 2,225,561 of Charles L. Henry and to an improve-- ment in the manner of raising and lowering such a mast.

In order to raise the mast shown in the Henry patent in the manner disclosed therein a cable is connected to the draw-works and strung over the short section of the mast and around pulleys connected to the tall section. When the drawworks is operated this cable is reeled in and the tall section of the mast swung up into upright position. Following this the lifting cable is disconnected from the draw-works and the drilling line connected to it. To lower the mast the drilling line must first be disconnected from the draw-works so that the lifting cable can be connected thereto. After the mast is down the cable lapping sections of different heights that are mounted on a support and that form, when cletachably connected together in upright position, a complete unitary mast. A line, preferably the drilling line, extends downwardly in the mast from its upper end, and means such as drawworks beside the mast is connected to this line for pulling it up and letting it down in the-mast. The tall section of the mast is hinged at its lower end to the mast support so that it can be swung i, and the upper portions 5 of the rear legs.

iownwardly into prone position along the ground.

F or raising and lowering the tall section a cable 5 connected to the other section of the mast and s adapted to extend into the tall section where .t can be connected to the line mentioned above. When they are thus connected the tall section if the mast can be swung downwardly to prone position by letting out the line, or raised to upright position by pulling it in.

The preferred embodiment of the invention is illustrated in the accompanying drawing in which Fig. 1 is a side view of our. mast structure with the tall section thereof in lowered position, its

upright position being shown by broken lines; Fig. 2 is a plan view of Fig. 1; Fig. 3 is an enlarged view of the short section of the erected mast taken from the draw-works end of the base; and Fig. 4 is an enlarged fragmentary side view of the connection of the top of th short section to the tall section of the mast.

Referring to the drawing, the bottom of a vertical oil well derrick or mast is mounted on a supporting base I so formed as to be slidable along the ground or transportable from one location to another if desired. The mast is made in two independent structural sections detachably connected together. One of these sections is relatively short and, as a four legged mast is illustrated, it includes the lower portions 2 of the two rear legs of the mast with suitable bracing members connected thereto (Fig. 3). As viewed in Fig. 1 these short legs 2 are supported by inclined braces 3 connected to the base. The upper ends of the braces 3 and legs 2 are pivotally connected together as shown in Fig. 4.

The other or tall section of the mast, shown extending along the ground in Figs. 1 and 2, consists of the remaining portion thereof and includes the front legs 4 which are mounted on base To helpv support and brace these rear legs diagonal bracing members 6 are connected thereto and to the lower ends of the front legs. Due to the formation of the mast in two independent sections it can be erected by fabricating or assembling it along the ground and then raising it to.upright position. For this purpose the lower ends of the front legs and braces3 are detachably connected to the working platform by hinges I to permit them to be swung independently in a vertical plane when the short rear legs 2 are disconnected from brackets 8 by which they normally are attached to the base. After the short section has been swung up into upright position and le s 2 connected to brackets 8, the tall section is swung upwardly in a manner to be described presently for attachment to the short section. This attachment may be accomplished by connecting the adjacent ends of the rear legs 2 and 5 by means of swinging eye-bolts 9 permanently connected to the tall section of the mast and detachablyconnected to the top of the short section, as shown in Fig. 4.

The draw-works for the well is shown mounted on base I and includes a hoisting drum I l which is rotated by suitable engines I2. A cable, I3 is shown in its dotted line position as extending from the drum up over the crown-block l4 and carried on trucks.

down into the upright mast where it suspends a traveling block 15 carrying hook l6 for supporting the drill stem used in rotary drilling.

When this mast is moved from one location to another it is divided into sections that can be The crown-block is left attached to the top of the mast and the traveling block is pulled up into the upper portion of the mast so that it is unnecessary to unstring the drilling line. Upon arrival at the new location the base I is set in place and the sections are assembled along the ground into the two main sections which are hinged to the base. At this time the legs 2 of the short section are collapsed against their braces 3 and the entire short section rests on braces 6 of the tall section lying in its prone position shown in Fig. 1. The short section is then swung up into upright position, such as by a line attached to its top and to a truck or other suitable device for pulling it. When this is accomplished the lower ends of the rear legs are connected to brackets 8 mounted on the base.

The next step is to raise the tall section of the mast. In accordance with this invention this is done by means of the drilling line 13, one end of which is connected to the base with its other end passing over a pulley I! mounted in the top of the short section and down to the draw-works where it is connected to the hoisting drum. A sling-like cable I8 is connected at its ends in any suitable manner to the top of the short section of the mast, and the central portion of the sling is extended down through the top side of the horizontal tall section of the mast and under pulleys l9 mounted therein. The middle of the sling is looped over the hook of the traveling block. By now operating the drawworks to reel in the drilling line the traveling block is pulled toward the crown-block whereby the sling, being pulled toward the top of the mast, must swing the tall section upwardly into upright position against the short section. As soon as the two sections have been connected together by the eye-bolts 9 the sling is removed from the hook' and tied to the side of the mast where it will not be in the way. The mast is lowered by merely reversing this procedure.

This method of raising a mast is not limited to the particular form of mast shown, for it is obvious that the mast can be built complete in one section along the ground and then swung up to upright position in the manner disclosed by connecting the ends of the sling to a suitable elevated support over which the drilling line 13 passes to the draw-works. 7

According to the provisions of the patent statutes, we have explained the principle and construction of our invention and have illustrated and described what we now consider to represent its best embodiment. However, we desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise. than as specifically illustrated and described.

We claim:

1. A mast structure comprising a support, a mast formed of two independent complementary overlapping sections of difierent heights mounted on said support, means for detachably connecting said sections together into a unitary mast when they are in upright position, a line extending downwardly in the tall section from its upper end, means for pulling up and letting down the line, the tall section being hinged at its lower end to said support for swinging downwardly into prone position along the ground, and a cable connected to said short section and adapted to extend into the tall section and to be connected to said line for lowering or raising the tall section when said line is let down or pulled up.

'2. A mast structure comprising a support, a mast formed of two independent complementary overlapping sections of different heights mounted on said support, means for detachably connecting said sections together into a unitary mast when they are in upright position, a line extending downwardly in the tall section from its upper end, means for pulling up and letting down the line, the tall section bein hinged at its lower end to said support for swinging downwardly into prone position along the ground, and a cable sling having its ends connected to the upper portion of said short section with its central portion adapted to extend into the tall section and to be connected to said line for lowering or raising the tall section when said line is let down or pulled up.

3. A mast structure comprising a support, a mast formed of two independent complementary overlapping sections of difi'erent heights mounted on said support, means for detachably connecting said sections together into a unitary mast when they are in upright position, a. drilling line extending downwardly in the tall section from its upper end, a hoisting drum mounted on said support and connected to said line for reeling it in and letting it out, and a cable connected to said short section and adapted to extend into the tall section and to be connected to said line for lowering or raising the tall section when said line is let out or pulled in.

4. A mast structure comprising a support, a mast formed of two independent complementary overlapping sections of different heights mounted on said support, means for detachably connecting said sections together into a unitary mast when they are in upright position, drawworks mounted on said support, a drilling line connected to the draw-works and extending upwardly outside of the mast and then downwardly in the tall section from its upper end, a hook suspended in the mast from said line, a cable sling attached at its ends to the upper portion of said short section with its central portion adapted to extend into the tall section and to be looped over said hook whereby to lower or raise the tall section when said hook is lowered or raised by the draw-works, and a pulley mounted in said short section for supporting said line when the tall section is lowered.

5. A mast structure comprising a support, a mast formed of two independent complementary overlapping sections of different heights mounted on said support, means for detachably connecting said sections together into a unitary mast when they are in upright position, a line extending downwardly in the tall section from its upper end, means for pulling in and letting out the line, the tall section being hinged at its lower end to said support for swinging downwardly into prone position along the ground, and a cable connected to said short section and extending outwardly into said tall section when the latter is prone, said cable being detachably connected to said line, and the tall section being provided with supporting means resting on the cable whereby the tall section is swung upwardly about its hinge connection when the cable is pulled by said line.

6. A mast structure comprising a support, a

mast formed of two independent complementary overlapping sections of difierent heights mounted on said support, means for detachably connecting said sections together into a unitary mast when they are in upright position, a line extending downwardly in the tall section from its upper end, means for pulling in and letting out the line, the tall section being hinged at its lower end to said support for swinging downwardly into prone position along the ground, a pair of laterally spaced pulleys mounted in the tall section, a cable sling having its ends connected to the top of said short portion with its central portion-extending outwardly and down into said tall section when the latter is prone, said central portion of the sling extending under' said pulleys in engagement therewith and being detachably connected to said line whereby the tall section is swung upwardly about its hinge connection when the cable is pulled by said line.

7. A mast structure comprising a base, a mast mounted on said base and hinged thereto for swinging downwardly into prone position along the ground, a line extending downwardly in the mast from its upper end, means for pulling up and letting down the line, an elevated supporting member, and a cable connected to the upper portion of said member and adapted to extend into the mast and to be connected to said line for lowering or raising the mast when said line is let down or pulled up.

HOMER J. WOOLSLAYER. ERWIN A. CAMPBELL. CECIL JENKINS.

Disclaimer 2,271,578.-Homer J. Woolslayer, Erwin A. Campbell and Cecil Jenkins, Tulsa, Okla. COLLAPSIBLE MABT ERECTION. Patent dated Feb. 3, 1942. Disclaimer filed Dec. 17, 1947, by the assignee, Lee 0'. Moore Corporation.

Hereby enters this disclaimer to all claims of said patent. [Oflicial Gazette January 18, 1948.] 

